Method of forming fibrous bell-mouth tube ends



Oct. 11, 1932. H. PARKER METHOD OF FORMING FiBRoUs BELL MOUTH TUBE ENDSOri inal Filed March 21, 1950 2 Shets-Sheet 1 Oct. 11, 1932. H. PARKER II 1,881,916

METHOD OF FORMING FIBROUS BELL MOUTH TUBE ENDS Origipal Filed March 21,1930 2 Sheets-Sheet 2 Patented Oct. 11, 1932 UNITED STATES AT N OFFICE,

BERLIN, NEW HAMPSHIRE, A CORPORATION OF MAINE METHOD OF FORMING FIBROUSDELI-MOUTH TUBE ENDS Original application filed March 21, 1980, SerialNo. 487,692. Divided and this application filed February i 28, 1931.Serial "No. 519,094.

This application is a division'of my copendlng application Serial No.437,692 filed March 21, 1930. The invention-relates to a method offorming fiber bell-mouth members foruse with fiber conduit. When fiberconduits are laid underground for telephone wires, electric cables,etc., the conduits are interrupted at intervals by man-holes throughwhich new wires may be threaded through the conduits, and in whichconnections can be made for branching wires, etc. The conduits open intothe man-holes on two or more sides. The wires or cables entering at oneside are usually bent around along the wall of the man-hole instead ofprojecting straight across, to keep the central portion of the man-hole,clear for workmen. In order to avoid sharp bends in the cables as theyenter'the man-holes, it is desirable that the conduits be laid withflared or bell-mouth ends to provide curved surfaces around-which thecables can bend as they enter a man-hole. If metal or tile conduits beused, such bell mouth ends can be cast or molded to any desired shape.Where fiber conduit is used,

- however, the problem of forming bell-mouth ends is more difficult,since the strength ofa fiber article depends largely on the method offorming it, owing to the fact that the strength of such an articlearises chiefly from the thoroughness with which the fibers areinterfelted. If, for example, fibrous tubing be made by winding a wetweb of pulp on itself on a mandrel, under pressure, the resulting tube,if properly dried, has comparatively great strength owing tothe-efiicient interfelting of the fibers caused by pressing the wetlayers together prior to drying. The mechanical strength of such tube isfar in excess of that of a tube of similar dimensions made by pressingpulp into a mold. In order to retain the strength of the fibrous tubingmade as described by winding a wet web on itself under pressure, thebell mouth embodying the present invention is preferably made tocomplete the structure.

According to the invention such a structure is preferably assembledwhile the materials are thoroughly wet, and the assembled HOWARIDPARKER,.OF BERLIN, NEW HAMPSHIRE, ASSIGNOR T0 BROWN COMPANY, OF

structure is thereupon subjected to high pressure which not only givesit its finished shape,

but also interfelts the separate parts into a well knitted unit.

For a more'complete understanding of the invention reference may be hadto the description thereof which follows, and to the drawings, ofwhich,'

. Figure 1 is an elevation of a section of fiber tubing, with an endslotted.

Figure 2, is an end View of the same.

Figure 3 is an elevation of asplit tube section with the end elementsbent outwardly.

Figure 4 is an end view of the same.

Figure 5 is a fragmentary section of the tube, wall (developed in ,aplane) after the insertion of gussets in the splits.

Figure 6 is a sectional View of a bell-mouth as it comes from the press.

Figure 7 is a similar view of a bell-mouth after being tooled to finalshape.

Figure 8 is a sectional view of pressing apparatus. v

In forming a bell mouth according to the invention, a. short length offiber tube 50 is thoroughly soaked in water. The end of thls section isslit longitudinally, as at 51, these slits being preferably uniformlyspaced around the circumference of the tube. The tube may be-spliteither before or after soaking. The soaked and split end of thetubeisthen spread, as shown in Figures 3 and 4, forming triangular openingsbetween the split end elements 52. This may be done by forcing the splitend down over a su table flaring mold such as is illustrated in Figure8. The side edges of the elements 52 may then be .bent slightly outward,as indicated 'at 55 in Figure 5. In the triangular openwardly, as shownin Figure 5. After the gussets are in place, the ,bent up edges may bepatted down flush to knit or felt together the abutting edges of thegussets .54 and the tube elements 52. This is preferably done while thetubular member 5.0 is on the flaring mold used for spreading theelements 52. The entire member 50 may now be pressed to shape the memberas a whole and to consolidate the seams'between the elements 52 and thegussets 54. This may be done by suitable apparatus such,'for example, asis illustrated in Figure 8, and is more fully illustrated and describedin my application Serial No.

- 437,692, hereinbefore referred to. After he ing pressed, thebell-mouth may be dried, treated with waterproofing material andmachined to its final shape.

Apparatus for presslng the bell-mouth is shown in Figure 8. Abell-shaped mold with suitable perforations 61 to carry off waterexpressed from the bell-mouth, is removably mounted on a standard 62 inwhich is a drain or suction line 63. The mold 60 may be covered with asuitable cloth b 64 which facilitates stripping the mold a er a bellmouth has been pressed to shape thereon.

Over the mold-is a heavy, removable cap- 65 within which is a rubberba g0r diaphragm 66. The diaphragm is tubular and is secured to the'capalong its entire upper and lower edges so as to form aclosed chamberwith the side wall of the cap. An opening 67 leads through the cap wallinto this chamber and communicates with a supply of pressure fluid suchas water. After a tube-portion 50 has been placed on the mold 60 and thessets have been suitably inserted, the capls lo'wered into place asshown, and firmly clamped in place." Water under pressure may then beintroduced through theinlet 67 to press the diaphragm 66 against thetube portion 50. This comp-acts the fibrous structure and expressesconsiderable of thewater from the member 50. After being ,pressed,-themember is ready for removal, drying and further treatment. a

I claim:

' 1. A method of joining together edge to .whereby wedge-shaped openingsare formed between, ad'acent elements, fittmg ssets of tube-wall. tickness into said opemngs, and

I felting together the abutting edges of said gussets and elements. I

3. A method of forming bell-mouthends,

which comprises longitudinally slitting an end portion of afiber tube,soaking said end portion in water, spreading the split end over a form,fitting wet fiber gussets into the widened slits to form a bell-mouth,workingthe abutting edges together, and applying pressure to the outersurface of said bell-mouth. 4:. -A method of forming fiber bell-mouthends, which comprises longitudinally slitting a wet end portion of afiber tube, pressing outwardly the material along said slits,

spreading theslit end portion over a bellshaped mold, fitting into thewidened slits gussets of material similar to that of said tube, saidgussets having their side edges upturned whereby a com lete bell-mouthstructure is formed with ridges along the seams, andpressing said ridgesflush with the adj acent surface.

In testimony whereof I have aflixed my signature.

. HOWARD PARKER.

